Device for moistening paper, fabrics, and like weblike material



,Dec. 1, 1942. c. G. ANDERSON 2,303,809

DEVICE FOR MOISTENING PAPER, FABRICS AND LIKE WEBLIKE MATERIAL Filed April 12, 1940' Fll9./.

(ZZZ- Patented Dec. 1, 1942 DEVICE FOR MOISTENING PAPER, FABRICS, AND LIKE WEBLIKE MATERIAL Carl Gustav Anderson, Stockholm, Sweden, as-

signor to Aktiebolaget Svenska Fliikttabrlken,

Stockholm, Sweden Application April 12, 1940, Serial No. 329,392 In Sweden March 1, 1939 3 Claims.

In the paper industry it is often necessary to moisten the paper after the glazing so as to give the same a moisture content suitable for printing.

According to the prior art, devices for this purpose usually consist of a casing of some kind through which the paper web to be moistened is moved and subjected to the action of moisture active air from a conditioning aggregate. The air used for the moistening at the best being saturated, but the moisture content often being not higher than 80%, these known devices, however, involve the drawback of requiring a very great space and, moreover, a great defect due to the necessity of keeping very great air quantities in circulation in order to obtain the desired moistening efiect.

The present invention relates to a device for overcoming these drawbacks. The method is substantially characterised in using such air in a casing for moistening paper, fabrics or other weblike material as has been supersaturated before entering the casing, i. e., the air has been caused to absorb water floating in the air in the form of mist, the supersaturated air being supplied at the end of the casing where the weblike material is taken out so that the material is subjected to the supersaturated air at least during the last stage of the moistening. This involves the advantage that the volume of the moistening casing and the quantity of the circulating air can be reduced. Another advantage obtained is also that the temperature in the casing is held constantly low owing to the evaporation of water in the casing in spite of heat being emitted when the paper absorbs vapour from the air.

The invention is illustrated on the accompanying drawing, which diagrammatically shows an embodiment of a device for carrying out the method above described. Fig. 1 shows a vertical longitudinal section and Fig. 2 a vertical cross section on line 11-11 in Fig. 1.

In the drawing reference numeral l indicates a closed casing through which the paper web 2 is moved in windings over a series of rolls 3 in the direction of the arrows a in a direction counter to the moist air, so that the most moist paper and the most moist air contact with each other, the greatest moistening effect being thereby obtained.

It has been shown that, owing to the counter current method, the glazing of the paper is not destroyed by supplying supersaturated air. Owing to the lower moisture content at the intake end the paper is gently treated at the beginning of the process, the higher moisture content of the air at the outlet end then having no unfavourable influence on the glazing. The rolls 3 are driven sectionally in order to neutralize changes of the length of the paper web which might be caused by the moistening.

The casing is divided by a number of partitions 4 in such a manner that a zigzagged channel is formed on both sides of the paper web. At the outtake end forthe web there are openings 5 and 6 above and beneath the paper web, through which openings supersaturated air is supplied to the apparatus, and at the intake end of the web there are provided corresponding openings 1 and.

8, through which the air is sucked out of the apparatus and returned to a moistening chamber 9, wherein the air is first cooled by washing with cold water from the water sprayers l0 and then moistened to supersaturation by condensation of vapour from a vapour sprayer II. The latter may be replaced by any equivalent devices for finely distributing water. In the opening 1 there may be provided vertical screens or the like (not shown) in order to prevent the cooling water from splashing in on to the paper web 2 against the air current. Moreover there is a drop-collector l3 which returns water, if any, to a basin l4, from which the water leaves through a draining outflow IS. The air is circulated through the apparatus by means of a fan l6, which is driven by means of a motor I! outside the apparatus. In front of the fan there is provided an eliminator l8, which prevents bigger water drops from being entrained by the air current but which lets through the finer water drops. Immediately behind the eliminator there is a heating device ill, by means of which, if required, the content of mechanically finely distributed water in the air may be adjusted to the desired value. From the heating device the air is led through a channel 20 to the openings 5 and 6. Also here there is a drop collector l3a, a basin Na and a draining outflow l5a as at the opening I. For the sake of simplicity steam pipes, water pipes etcetera are not indicated, the same not being objects of the invention.

The devices described above may be multiplied either by placing one after the other or by placing two or more side by side. The invention is not confined, of course, to any special method or any special device for feeding the object to be moistened.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An apparatus for moistening paper, fabrics or similar material in web form, comprising a casing, air moistening means within said casing, a horizontal partition dividing said easing into a horizontal channel, adjacent its top, and a web treating chamber, vertical partitions at each end of said casing providing channels communi eating with said horizontal channel and said web treating chamber, spaced vertical bailles within said chamber providing a zig-zag channel, rollers within said zig-zag channel for movably supporting a web, means for circulating the air through said channels, a sprayer for vapor located in one of said communicating channels, a drop catcher in said casing beneath the moistening means and sprayer, and a heating device in said casing for regulating the relative humidity of the air.

2. An apparatus for moistening papers, fabrics or similar material in web form comprising a casing, air moistening means within said casing, a partition dividing said easing into a channel and a web treating chamber, partitions extending at right angles to said first mentioned partition adjacent the ends of said casing providing channels communicating with said first mentioned channel and said web treating chamber, spaced baiiles located within said chamber forming a zi zag channel, means within said zig-zag channel for movably supporting a web, means for circulating the air through said channels, a sprayer for vapor in said casing, a drop catcher in said easing beneath the moistening means and sprayer, and a heating device in said casing for regulating the relative humidity of the air.

3. An apparatus for moistening papers, fabrics or similar material in web form comprising a casing, air moistening means within said casing, a horizontal partition dividing said easing into a horizontal channel, adjacent its top, and a web treating chamber, vertical partitions at each end of said casing providing channels communicating with said horizontal channel and said web treating chamber, spaced vertical battles-within said chamberproviding a zig-zag channel, means within said zig-zag channel for movably supporting said web and a fan for circulating the air through said channels.

CARL GUSTAV ANDERSON. 

